[ahmed]

Hi, can anyone help:[
My Inspiron psu (PA-10) is no longer "visible" to the laptop, i.e. the normal green battery charging led no longer lights up.
The laptop works perfectly off the battery but there ain't a lot of capacity left in it now, especially as I can't charge it.

It could be something as simple as a dry joint on the pcb mounted power socket or a damaged contact on it, but more likely , I think I blew something when I initially suspected the PA-10 and cut the cord up, and accidentally put the wrong voltage through to the laptop (I believe there are two voltages present on these psu's plus two separate earth returns) .

I have removed all the screws off the back and have looked at the motherboard but that's all I can do.

Given that I have had this laptop for only 18 months after buying it for £1500, I am thinking of plan B: work out the battery's pinout which should allow me to recharge the battery independent of the laptop and as a by-product this should allow me to make an adapter of some sort to power the laptop via the battery connectors..
But that's where I'm stuck - there are 9 battery pins on the laptop and 9 connectors on the battery - how many individual Lithium Ion/polymer cells are there, are any in parallel to increase capacity etc?
What is the nature of the connectivity between them ( I have seen the characteristic Lithium 3.7v - 3v nominal voltage on some of the pins: can I be sure these are individual cells as I noted on the battery casing the battery is supposedly 11.1v - can the laptop run on only 3 lithium cells, if so, why 19v dc input from the PA-10 psu?).
There seems to be a common negative four pins in from the left.But when I tried to charge with a special radio control hobby charger I had problems, perhaps it's not a single LiIon pack?
I'm thinking about my next move: do I try to buy an old compatible dell to use to charge my battery to allow me to remove my sensitive data (encrypted, but still it's a worry) and then give to a 'professional'
or do I try to buy a motherboard off ebay for £50 and diy? ( I'm worried about bios and stuff...what about the graphics stuff - is that all on a removable IC?

does anyone do an external (ie off laptop) battery charger ?


Any thoughts?

[dice14u]

honesty you are grasping at straws when trying to decode their little pinsets. Yes an external type charger is available. As for your psu if you put it to too many volts DC then your battery could have simply just lost the chemical ability to charge reversing the negative and positive on some equipment might also cause complete equipment failure. I would not be playing around with it more information about exactly what you did would be necessary to give you an exact answer. Hitting something with too many amps however will not damage the object as it will take only as many amps as it can handle and not call for anymore.
All of those different pins are different voltages and their specific returns like some things might use 12 volts while others use 3.3 or whatever. Trying to guess which pins do which will take a voltmeter and a process of deduction trying almost every combination of pins to find the negative and positive of each potential difference. Maybe the pinset is online for you. Or find an external power charger as they are out there.
And yes everything is removable from the laptop. But buying the motherboard alone is pretty much impossible.

[ahmed]

Hi, thanks for the rely. I have sourced several motherboards on ebay, they seem to be originating out of the States, some new, some refurbished. I am now struggling with the correct Dell part number for the motherboard - where is this located - anyone know?

The battery is a Lithium ion, it can only be in cell groups of 3.7v, but there may be pairs or single cells in parallel to increase the capacity, anyway, i have given up trying to figure out the internal cell connectivity.

My current course of action is to correctly identify my motherboard part number and then acquire one through ebay or one of the myriad of "laptop repair/spares" suppliers out there. Then it should be a matter of transferring my Ram, Processor chip, Wifi module, modem module, and graphics card to the replacement motherboard...right guys?

The only thing I worry about is the Bios - but this will be supplied in a re-writable IC on the new motherboard should it not?

Anyone foresee any problems I have not mentioned...?